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This is like sample but has an "enter/exit" flag with it. This can be useful when you want to provide tracing instead of sampling. We use a different frame type so that we can denote that this isn't traditional sampling, and the flag can be used to find the next exit for the current enter for calculating durations. The entire stack trace is provided to make things easier on tools which may want to deal with indirect functions that were not instrumented but can be unwound. That may allow for tooling to give the user some insight that it's not *just* this function entering, but some functions before it were entered too. This also adds a SysprofTracer instrument which will preload a libsysprof-tracer-6.so into the process providing the __cyg_profile_func_enter() and __cyg_profile_func_leave() hooks.
Sysprof is a sampling profiler that uses a kernel module to generate stacktraces which are then interpreted by the userspace program "sysprof".
See the Sysprof homepage for more information.
Merge requests and bug reports should be sent to sysprof's repository on GNOME's GitLab instance. For general discussion and questions, you can create a new topic in GNOME's Discourse.
The former mailing list is archived in https://mail.gnome.org/archives/sysprof-list/.
Debugging symbols
The programs and libraries you want to profile should be compiled
with -fno-omit-frame-pointer and have debugging symbols available,
or you won't get much usable information.
Building Sysprof
You need some packages installed. The package names may vary depending on your distribution, the following command works on Fedora 36:
sudo dnf install gcc gcc-c++ ninja-build gtk4-devel libadwaita-devel
Then do the following:
meson --prefix=/usr build
cd build
ninja
sudo ninja install
WARNING: ninja install will mostly install under the configured install
prefix but installs systemd service configuration directly in the system
default location /usr/lib/systemd so it won't work without root privileges,
even if the install prefix is a user-owned directory.